[GHC] #10423: Can't infer Monad n from (Monad m, m ~ n)

[GHC]

#10423: Can't infer Monad n from (Monad m, m ~ n)
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        Reporter:  Feuerbach         |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler (Type    |                 Version:  7.11
  checker)                           |                Keywords:
      Resolution:                    |            Architecture:
Operating System:  Unknown/Multiple  |  Unknown/Multiple
 Type of failure:  None/Unknown      |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"b1b2b44a86a34dae9eadd27af507c8b2c847ae2d/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="b1b2b44a86a34dae9eadd27af507c8b2c847ae2d"
 Test Trac #10423
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10423#comment:3>
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